There's a merged pull request on the void-packages repository

musl: update realpath/readlink and add gettid
https://github.com/void-linux/void-packages/pull/37646

Description:
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#### Testing the changes
- I tested the changes in this PR: **briefly**

Everything builds.
The realpath/readlink patches were stated to be working here (let me know if there are any issues though):
https://github.com/void-linux/void-packages/pull/33372

Afaict, nothing important related to how  `__pthread_self()->tid` works was changed between our version and when `gettid()` was introduced, but it should still be tested.

I'm not running musl atm though so its a little hard for me to test it currently so feedback would be appreciated.

https://github.com/void-linux/void-packages/pull/37628#issuecomment-1163607702

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